Regulated voltage system for detecting suspended matter in fluids



H. c. GRANT, JR 2,069,160

REGULATED VOLTAGE SYSTEM FOR DETECTING SUSPENDED MATTER IN FLUIDS Jan. 26, 1937.

Filed Sept. 1, 1933 NNN INVENTOR bar/y ('0 ATTORNEY Patented Jan. 26, 1937 DETECTING SUSPENDED IN FLUIDS MATTER Harry Campbell Grant, In, New York, N. Y., assignor to Walter Kidde & Company, Inc., Bloomfield, N. 1., a corporation of New York Application September l, 1933, Serial No. 687,836 2 Claims. (01. 177-311) The present invention relates broadly to smoke or other suspended matter detecting apparatus of the type employing a source, of light directed upon a light-sensitive element with a fluid our- 5 rent flowing along the path of the beam of light directed from the source of light upon the lightsensitive element and in which the presence of smoke or other suspended matter in the fluid current acts to decrease the intensity of the light to falling upon the light-sensitive element and to thereby cause analarm signal to be rendered.

In such apparatus as previously employed, it has been found that ifthe light-sensitive element v circuit is adjusted to give detection for a reason- 15 ably light smoke density, it will also give false smoke alarms for a drop in the line voltage as little as four volts, it being understood, of course, that a drop in the line voltage will cause a decrease in the intensity of the light emitted by the source of light, being the same condition as is produced by the presence of smoke in the fluid current flowing along the path of the beam of light directed from the source of light upon the lightsensitive element.

25 The desirability of having a regulated voltage for detecting apparatus of the type referred to will therefore be apparent.

It is accordingly an, object of the present invention to provide a regulated voltage system for 30 detecting the presence of suspended matter in fluids. Y

provide-a suspended matter detecting apparatus of the type broadly referred to, in which no suspended matter alarm is given upon a decrease in the intensity of the main light source due to other causes than the presence of suspended 5 matter in the fluid current.

These, and other objects of the invention, not specifically enumerated above, will be apparent as the invention is described in greater detail in connection with the single figure of the accompanying drawing, which is a conventional view showing the electrical circuits and connections of a regulated voltage system for detecting suspended matter in fluids in accordance with the present invention.

For convenience in describing the subject-matter of the present invention, the description will first be directed to the voltageregulating arrangement, which may be of any suitable type, but which in the present instance is substantially in accordance with Figure 1 of my co-pending application for Letters Patent of the United States entitled Voltage regulation, Serial No. 687,835

It is a further object of the present invention to provide a system of the type referred to in which a drop in the voltage applied to the system, as requiring an adjustment of the" voltage, causes the smoke alarm signals to be rendered inoperative during the time that the voltage is being adjusted to its proper value. I

It is another object of the invention to provide 40 a system of the type referred to in which adrop in the voltage applied to the system of a magnitude beyond the adjusting range of the voltage regulating arrangement will cause the smoke alarm signals to be rendered inoperative and a is trouble signal to be instituted.

It is still another object of the invention to provide. a system of the type referred to in which the voltage regulating arrangement is deenergized upon failure of the main light source of 50 ,thesmoke detecting arrangement, so as to protect 1 the galvanometer of the voltage regulating arrangement againstthe heavy overload which would result upon the removal of the current passed through the main light source.

55 It is a still further object of the invention to and flled'on even date herewith, the same ref-i erence characters having been employed in both applications, wherever possible, for all elements which are the same, different reference characters being employed for those additional elements required for bringing the voltage regulating arrangement into cooperation with the smoke detecting arrangement of the present invention.

Referring now to the drawing, the unregulated voltage is applied from the positive POS. of the source of electric potential to the terminal line E and from the negative NEG. to the terminal line 0. The regulated positive voltage is obtained from terminal L1 (111) of the voltage regulator terminals, the negative terminal being shown at La (IV). As explained in my herein above referred to co-pending application, when the voltage across terminals E and 0 drops, galvanometer relay G. R. deflects to the left, causing the relay I to operate through a circuit from negative terminal line 0, through wires IOI, I02, I03, through contact I04 .of relay I05, through wire I06, through terminal IV of the voltage regulator terminals, through wire I01, through resistance 2, through the now closed contact ,3, through the relay I, through the normally closed contact 4, and through wires 5, 6 and l to the positive terminal line E, causing the relay I to operate. The operation of the relay I first of all closes the contact 8, permitting a current to flow from the positive terminal line E, through wires 1, 6 and 9, through contact 8, through armature I0, through 55 wires II and I2, through the field I3 or the voltage regulator motor I4, through wires I5 and H,

'to the negative terminal line 0. Then, closing of the contact I0 of the relay I permits current to voltage regulator motor I4, through the wire 28,

through the now closed contact of the relay 2|, through the armature 30, and through wire H to the negative terminal line 0. Since both the armature and the field I3 of the voltage regulator motor H are now connected to positive and negative, this motor causes the motor driven rheostat W to turn so as to reduce its resistance and bring the regulated voltage at terminal Ll (e) to'its proper value. When the voltage at terminal L1. (e) is correct, e'contacts-of the galvanometer relay G. R; cl r, releasing the relay i and the relay 2|, permitting the voltage regulator motor to stop.

it will also be noted that the relay] controls a normally closed contact I08 which, as will be described hereinafter, controls the energization of the smoke signals of the smoke detecting arrangement. Since, as pointed out at the beginning of this specification, a decrease in the line voltage as little as four volts will cause a false smoke alarm to be given, and since therelay I is operated upon a drop in the voltage across terminals E and 0, contact I00 will be opened upon operation of the relay I and will remain open all during the time that the voltage is being adjusted to its proper value. Consequently, no false smoke alarm will be given, as the smoke signals cannot be rendered while contact I00 is open.

-2, through the now closed contact 32, through the relay 3|, throughthe normally closed contact 33, through wires 34 and ,l to the positive terminal line E. The operation of the relay 3| closes the contact 35, permitting a current to how from positive terminal line E, through wires 1, 30 and "30,

through armature 31 'of the relay 3|, through contact 35, through wires II and I2, through field I3 of the voltage regulator motor II, and

through wires I5 and II to negative'terminalline 0, thus energizing the field I3 in exactly the same sense as it is energized by operation of the relay I. However, the relay 2| is not energized upon operation of the relay 3| (as it is upon operation of the relay I), so that the direction of the current through the armature oi. the voltage regulator motor II is reversdycausing the motor to turn in the opposite direction and to bring the regulated-voltageat terminal L (e) to its proper value. In accomplishing this, the connection from-the positive terminal'lin E is through the contact 30 of-the relay 2| to the wire 23 connecting to one side of the armature of the motor II,

instead of through contact of therelay 2-i to the wire 2'! connecting to the other side of the armature of the motor I4. I

It, will be noted that if the voltage changes sufliciently, the motor driven rheostat W will reach its limit in one direction or another. While the regulator as described is operable to produce a constant regulated voltage from asource of electric potential varying over a. wide range, it will not regulate over the entire range, and it is accordingly necessary to provide means for preventing mechanical injury to the rheostat and its driving mechanism. Limit switches are accordingly provided on therheostat and arranged in such a manner that their circuits are opened before the mechanical limit of the rheostat is reached. These limit switches are shown at '40" and 4| for the relays I and 3| respectively. Operation of the element 40' of the limit switch 40'--40" when the rheostat W has reached one limit of its motion disconnects the relay l by breaking its energizing circuit at the contact 4 of the limit switch, causing the voltage regulator motor I4 to stop. Since, however, deenergization of the relay I causes closingof contact I08, which as already explained controls the energization of the smoke alarm signals, element 40" of the limit switch 40'-40" is operated simultaneously with the operation of the element id of the limit switch, resulting in the opening of contact I 09, which acts similarly to contact I08 to control the energization (and deenergization) of the smoke alarm signals.

On the other hand, opening or the limit switch 4| when the rheostat W has reached the other limit 'of its motion disconnects the relay 3| by breaking its energizing circuit at the contact 33 of the limit switch, likewise causing the voltage regulator motor M to stop. r At the same time that the contact 4 of the limit switch 00' |0" is opened, the contact 42 of the limit switch is closed, thuscompleting acircuit from the positive terminal line E, through wires I, 6 and. 5, through contact 82, through wire 53, through wire IIO, through a trouble bell 44 and a trouble lamp 05 in parallel, and through wires 46, HI and IOI to negative terminal line 0. Similarly, at the same time that the contact-33 of the limit switch 4| is opened, the contact 3| of the limit switch is closed, thus completing a cire cuit from positive terminalline E, through wires iand 34, through contact 41, through wires 48 and H0, through the trouble bell 40. and trouble lamp in parallel, and through the wires 46, 'I II and IM to negative terminal line 0. -It will therefore be seenthat trouble signals are given when the unregulated line voltage is too high or too low, i; e., beyond the adjusting range of the regulator, so that proper steps may be taken'at onceto correct the voltage directly at the source. A switch 49 is provided. in the circuit of the trouble bell so that the trouble bell may be stopped, but he trouble lamp 5 remains lighted until the trouble has been corrected.

. Certain other features of construction of the voltage regulating arrangement having no di-- rect bearing on the present invention have not been described herein, as the manner of operation of the same can be ascertained from my herein above referred to co-pending application.

The smoke detecting arrangement of the present invention will now be described with reference to the drawing, in which I I2 is the main light source from which light is directed upon :the light-sensitive element m, the latter of which is of the photo-voltaic type requiring no aocaioo source of electric potential for operation thereof.

As it is one of the objects of the present invensource H2. The voltage is therefore maintained constant across the series circuit comprising the relay I05, the main light source I I2 and the meter control resistance H5. The meter control resistance H5 is provided to permit the manual adjustment of the voltage across the main light source H2 to increase the light output thereof as the optical system becomes dirtier with increasing time and as the light output decreases due to the aging of the lamp; thismanual control requiring infrequent adjustment. Failure of the main light source H2 permits the release of the relay I05,-opening the contact I04, and closing the contact H6.

Opening of contact I04 of the relay I05 serves a double purpose, first of all breaking the connection from the negative terminal line 0, through wires IOI, I02 and I03, through contact I04 and through wire I II to one side of the smoke alarm signal gong H8 and the smoke alarm signal lamp I I9, preventing operation of the smoke alarm signals, which would give a false alarm upon the extinguishing of the main light source H2. Opening of the contact I04 also results in breaking the connection from the negative terminal line 0, through wires IOI, I02 and I03, through contact I04, and through wire I06 to the negative terminalLz of the voltage regulating arrangement, thus causing deenergization of the voltage regulatingarrangement upon failure of themain light source H2, so as to protect the galvanometer G. R. of the voltage regulating arrangement against the heavy overload which would result upon the removal of the current passed through the main light source.

Of course, closing of contact H6 of the relay I05 gives a trouble signal to indicate that the main light source I I2 has failed, the trouble signal connections being from the positive terminal line E through wire I20, through contact H6, through the trouble bell 44 and the trouble lamp 45- in paralleljand through wires 46, III and IOI to the negative terminal line 0'.

When the proper light intensity is directed from the main. light source H2 upon the lightsensitive element a, the contact 121 of the main galvanometer relay G. R. is held open. Introduction of smoke, reducing the light intensity on the light-sensitive element, permits the contact I2I to close, causing a current'to flow from the positive terminal line E to the terminal I of the voltage regulator terminals, through the motor driven rheostat W, through the wire I22, through the terminal Ll (III) through wire II3,

' through the main smoke relay I23, through contact I2I of the main galvanometer relay M. G. R...

' I24, and through wires I02 and IM to -the negativeterminal line 0, causing operation of the main smoke relay I23. Resistance I24 is used to reduce, the current to the proper operating value of the relay I23. The condenser I25 shown to the left of the relay I05 is connected line E.

across the relay I23 to eliminate arcing of the contacts of the main galvanometer relay M..G. R. The one side of the condenser I25 connects directly with the main smokerelay I23. The other side connects directly with the positive terminal 5 As the other side of the main smoke relay I23 connects to the positive terminal line E through the motor driven rheostat W and the resistances I20 and I21, the condenser I25 is actually connected across relay I23 in series with 10 these resistances.

Operation of relay I23 closes contact I28, causing current to flow from the positive terminal line E, through terminal II of the voltage regulator terminals, through wires I, 6. 5 and I0, through l5 armature 20 of the relay 'I,-through contact I08, through element 40 of the limit switch, 40'40", through contact I08, through terminal VI, through wire I29, through contact I28 of the main smoke relay I23, through the smoke alarm 20 signal gong H8 and the smoke alarm signal lamp H9 in parallel, through wires H1 and I30, through contact I04 of relay I05, and through wires I03, I02 and IOI to. the negative terminal line 0, thus causing operation of the gong H8 25 and the lamp I I9. Operation of the gong switch I3I cuts the operating circuit of the smoke alarm signal gong H8, but leaves the circuit through the smoke alarm signal lamp intact. As previously pointed out, contact I04 is controlled by 30 relay,l05, which is the supervising relay for the main light source II2; so that failure of the main light source H2, with consequent deenergization of the relay I05, cuts the energizing circuit of the main smoke alarm signals H8 and H9. At the same time contact I04 cuts the energizing circuit of the voltage regulating arrangement, as already previously described.

From the foregoing description it will be seen that I have first of all produced a practicable regulated voltage system for detecting suspended matter in fluids, and that I have accomplished all of the various objects set out at the beginning of this specification. It will of course be understood that any suitable voltage regulating arrangement may be employed in combination with my suspended matter detecting arrangement, and that I have simply employed the voltage regulating arrangement described in my hereinbefore re- 5 ferred to co-pending application as a matter of convenience and by way of example. In fact, my invention is capable of being carried out inw various styles of execution, and I accordingly do not wish to be limited, save as defined in the 55 appended claims.

I claim: I

1. In combination an apparatus of the type employing a source of light directed upon a lightsensitive element and an alarm controlled by a. 0

decrease of the intensity of light falling upon the light-sensitive element, voltage regulating means for maintaining substantially a constant regulated voltage on the source of light, said voltage regulating means being energized from a source 65 of electric potential subject to fluctuation involtage, and means'to protect the voltage regulating means against the overload which would result upon failure of the source of light due to the removal of the current demand of the source 70 of light comprising a normally energized relay in the energizing circuit of the source of light, and a normally closed contact in the energizing circuit of the voltage regulating means, said contact being controlled by said relay and being broken upondeenergization of the relay due to failure of the source of light.

2. In combination an apparatus of the type employing a source of light directed upon a lightsensitive element and an alarm controlled by a decrease of the intensity of light falling upon to prevent a false alarm signal upon a decrease in voltage below the desired constant voltage comprising a normally closed contact in the energizing circuit of the alarm which is opened upon operation of the voltage increasing means and. closed again upon cessation of operation of "the voltage increasing means, and means to prevent a false alarm signal whenever the voltage changing means reaches the limit of its voltage increasing efiect at a time when the regulated voltage is still below the desired constant voltage comprising a second normally closed contact in the energizing circuit of the alarm which is opened whenever the voltage changing means reaches the limit of its voltage increasing efiect.

HARRY CAMPBELL GRANT, JR.- 

